/****************************************************************************
 *
 * Copyright 2016 Samsung Electronics All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied. See the License for the specific
 * language governing permissions and limitations under the License.
 *
 ****************************************************************************/
/****************************************************************************
 * fs/vfs/fs_fcntl.c
 *
 *   Copyright (C) 2009, 2012-2014 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <gnutt@nuttx.org>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name NuttX nor the names of its contributors may be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 ****************************************************************************/

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <tinyara/config.h>

#include <stdarg.h>
#include <fcntl.h>
#include <errno.h>
#include <assert.h>

#include <tinyara/fs/fs.h>
#include <tinyara/net/net.h>
#include <tinyara/sched.h>
#include <tinyara/cancelpt.h>

#include "inode/inode.h"

/****************************************************************************
 * Pre-processor Definitions
 ****************************************************************************/

/****************************************************************************
 * Private Functions
 ****************************************************************************/

/****************************************************************************
 * Public Functions
 ****************************************************************************/

/****************************************************************************
 * Name: file_vfcntl
 *
 * Description:
 *   Similar to the standard vfcntl function except that is accepts a struct
 *   struct file instance instead of a file descriptor.  Currently used
 *   only by aio_fcntl();
 *
 ****************************************************************************/

#if CONFIG_NFILE_DESCRIPTORS > 0
int file_vfcntl(FAR struct file *filep, int cmd, va_list ap)
{
	int err = 0;
	int ret = OK;

	/* Was this file opened ? */

	if (!filep->f_inode) {
		err = EBADF;
		goto errout;
	}

	switch (cmd) {
	case F_DUPFD:
		/* Return a new file descriptor which shall be the lowest numbered
		 * available (that is, not already open) file descriptor greater than
		 * or equal to the third argument, arg, taken as an integer of type
		 * int. The new file descriptor shall refer to the same open file
		 * description as the original file descriptor, and shall share any
		 * locks.  The FD_CLOEXEC flag associated  with the new file descriptor
		 * shall be cleared to keep the file open across calls to one of the
		 * exec functions.
		 */

	{
		ret = file_dup(filep, va_arg(ap, int));
	}
	break;

	case F_GETFD:
	/* Get the file descriptor flags defined in <fcntl.h> that are associated
	 * with the file descriptor fd.  File descriptor flags are associated
	 * with a single file descriptor and do not affect other file descriptors
	 * that refer to the same file.
	 */

	case F_SETFD:
		/* Set the file descriptor flags defined in <fcntl.h>, that are associated
		 * with fd, to the third argument, arg, taken as type int. If the
		 * FD_CLOEXEC flag in the third argument is 0, the file shall remain open
		 * across the exec functions; otherwise, the file shall be closed upon
		 * successful execution of one  of  the  exec  functions.
		 */

		err = ENOSYS;
		break;

	case F_GETFL:
		/* Get the file status flags and file access modes, defined in <fcntl.h>,
		 * for the file description associated with fd. The file access modes
		 * can be extracted from the return value using the mask O_ACCMODE, which is
		 * defined  in <fcntl.h>. File status flags and file access modes are associated
		 * with the file description and do not affect other file descriptors that
		 * refer to the same file with different open file descriptions.
		 */

	{
		ret = filep->f_oflags;
	}
	break;

	case F_SETFL:
		/* Set the file status flags, defined in <fcntl.h>, for the file description
		 * associated with fd from the corresponding  bits in the third argument,
		 * arg, taken as type int. Bits corresponding to the file access mode and
		 * the file creation flags, as defined in <fcntl.h>, that are set in arg shall
		 * be ignored. If any bits in arg other than those mentioned here are changed
		 * by the application, the result is unspecified.
		 */

	{
		int oflags = va_arg(ap, int);

		oflags &= FFCNTL;
		filep->f_oflags &= ~FFCNTL;
		filep->f_oflags |= oflags;
	}
	break;

	case F_GETOWN:
	/* If fd refers to a socket, get the process or process group ID specified
	 * to receive SIGURG signals when out-of-band data is available. Positive values
	 * indicate a process ID; negative values, other than -1, indicate a process group
	 * ID. If fd does not refer to a socket, the results are unspecified.
	 */

	case F_SETOWN:
		/* If fd refers to a socket, set the process or process group ID specified
		 * to receive SIGURG signals when out-of-band data is available, using the value
		 * of the third argument, arg, taken as type int. Positive values indicate a
		 * process ID; negative values, other than -1, indicate a process group ID. If
		 * fd does not refer to a socket, the results are unspecified.
		 */

		err = EBADF;			/* Only valid on socket descriptors */
		break;

	case F_GETLK:
	/* Get the first lock which blocks the lock description pointed to by the third
	 * argument, arg, taken as a pointer to type struct flock, defined in <fcntl.h>.
	 * The information retrieved shall overwrite the information passed to fcntl() in
	 * the structure flock. If no lock is found that would prevent this lock from being
	 * created, then the structure shall be left unchanged except for the lock type
	 * which shall be set to F_UNLCK.
	 */

	case F_SETLK:
	/* Set or clear a file segment lock according to the lock description pointed to
	 * by the third argument, arg, taken as a pointer to type struct flock, defined in
	 * <fcntl.h>. F_SETLK can establish shared (or read) locks (F_RDLCK) or exclusive
	 * (or write) locks (F_WRLCK), as well  as  to  remove  either  type  of  lock  (F_UNLCK).
	 * F_RDLCK, F_WRLCK, and F_UNLCK are defined in <fcntl.h>. If a shared or exclusive
	 * lock cannot be set, fcntl() shall return immediately with a return value of -1.
	 */

	case F_SETLKW:
		/* This command shall be equivalent to F_SETLK except that if a shared or exclusive
		 * lock is blocked by other locks, the thread shall wait until the request can be
		 * satisfied. If a signal that is to be caught is received while fcntl() is waiting
		 * for a region, fcntl() shall be interrupted. Upon return from the signal handler,
		 * fcntl() shall return -1 with errno set to [EINTR], and the lock operation shall
		 * not be done.
		 */

		err = ENOSYS;			/* Not implemented */
		break;

	default:
		err = EINVAL;
		break;
	}

errout:
	if (err != 0) {
		set_errno(err);
		return ERROR;
	}

	return ret;
}
#endif							/* CONFIG_NFILE_DESCRIPTORS > 0 */

/****************************************************************************
 * Name: fcntl
 ****************************************************************************/

int fcntl(int fd, int cmd, ...)
{
	FAR struct file *filep;
	va_list ap;
	int ret;

	/* fcntl() is a cancellation point */
	(void)enter_cancellation_point();

	/* Setup to access the variable argument list */

	va_start(ap, cmd);

	/* Did we get a valid file descriptor? */

#if CONFIG_NFILE_DESCRIPTORS > 0
	if ((unsigned int)fd < CONFIG_NFILE_DESCRIPTORS) {
		/* Get the file structure corresponding to the file descriptor. */

		filep = fs_getfilep(fd);
		if (!filep) {
			/* The errno value has already been set */

			va_end(ap);
			leave_cancellation_point();
			return ERROR;
		}

		/* Let file_vfcntl() do the real work */

		ret = file_vfcntl(filep, cmd, ap);
	} else
#endif
	{
		/* No... check for operations on a socket descriptor */

#if defined(CONFIG_NET) && CONFIG_NSOCKET_DESCRIPTORS > 0
		if ((unsigned int)fd < (CONFIG_NFILE_DESCRIPTORS + CONFIG_NSOCKET_DESCRIPTORS)) {
			/* Yes.. defer socket descriptor operations to net_vfcntl() */
			ret = net_vfcntl(fd, cmd, ap);
		} else
#endif
		{
			/* No.. this descriptor number is out of range */

			ret = EBADF;
		}
	}

	va_end(ap);
	leave_cancellation_point();
	return ret;
}
